Despite the best efforts of software developers, spreadsheet application programs (“SAPS”), such as the “EXCEL” application program manufactured and sold by Microsoft Corporation of Redmond, Wash., inevitably fail at one time or another. For example, network connectivity problems, viruses, and anti-virus software may cause failures in a SAP. Unhandled failures may result in a crash, at which time the operating system terminates the application program execution. When a program crashes, all of its state data is lost. As a result, users that were in the process of modifying a spreadsheet, may lose substantial amounts of information. Information loss may create a significant amount of work and frustration to users.
To minimize the information lost as a result of a crash, different approaches have been taken. For example, one prior art method comprises performing a normal save of the open document immediately after a failure is detected as if the failure never occurred.
Attempting to save the document after a failure, however, can often cause another failure while saving the document. If the save attempt is unsuccessful then the modified changes in the document are lost and no other attempt is made to recover the information. Furthermore, even if the save attempt is successful, the document may include corruption that prevents the application program in which the failure occurred from reopening the document.
Because the application program may not be able to open corrupt files, the user may still lose substantial amounts of work. Therefore, unless the open files are repaired before they are saved to non-volatile memory, merely saving the files after a failure in the SAP may not provide any benefit to the user.
Accordingly, there is a need for a method and system for saving the ????. There is also a need for a method and system for verifying the contents of an open file to determine whether the file has been corrupted, possibly as a result of the same problems that led to the application failure.
There is still an additional need for a method and system for verifying the contents of an open file that is sufficiently robust to recover information from severely corrupt files.